• hepatocellular carcinoma;
  • immunohistochemistry

Abstract: Aims/Background: Although serum PIVKA-II has been widely used as a tumor marker for hepatocellular carcinoma (HCC), little information is available concerning tissue PIVKA-II, and detection of tissue PIVKA-II in paraffin-embedded tissue specimens of HCC is also considered difficult. Methods: Paraffin-embedded HCC tissues obtained at autopsy from 22 patients were subjected to immunohistochemical staining using the antibody MU-3 (Eisai Co., Ltd.) after microwave antigen retrieval. Results: PIVKA-II was mainly detected in the cytoplasm of HCC cells. The intensity of tissue PIVKA-II staining was not correlated with serum PIVKA-II levels or with the histological differentiation of HCC. However PIVKA-II staining tended to be more intense in tissue from patients with portal tumor thrombus, distant metastases, or a longer duration of HCC. Conclusion: This method of immunohistochemical staining is easy and simple to use and may be helpful for detecting tissue PIVKA-II in paraffin-embedded HCC specimens.